As the first vuvuzelas of the 16-nation championships co-hosted by Poland and Ukraine blared in the Polish capital fans both young and old flooded into the city centre, some beating drums, others singing, all keen to see Poland clobber Greece at the evening inaugural match.

A torrential rain storm failed to dampen the high spirits among them, some clad in Yeti, octopus and clown costumes, but most sporting Poland’s bright red-and-white. Femen, Ukraine’s media savvy topless feminists added to the pre-match fever at Warsaw’s brand new national stadium, baring their breasts and screaming “F**k Euro” to denounce the games they claim will lead to a spike in prostitution and sex trafficking in both host countries.

“The atmosphere is heating up,” said Karol Niedbal, a 27-year-old pharmaceutical company employee, an early bird fan heading to the nearby national stadium with friends hours before the match.

Poland is expecting up to one million fans to pour into the country before the championships wind up in the July 1 final in Ukraine’s capital Kiev. “This may be the only event on this scale here in our lifetime, it can’t be missed,” Tomasz Woldan, a 33-year-old IT specialist, told AFP in the huge square set aside for fans with stands and giant television screens.

Dancers performing at the opening ceremony for Euro 2012. Pic/AFP

While the decision by European football's governing body UEFA to hold its top tournament in states once behind the Iron Curtain for the first time is showcasing the hosts, concerns over racism, fan safety and political rancour are casting a shadow.

Netherlands captain Mark van Bommel has slammed racist “monkey chants” during a public training session in the southern Polish city of Krakow. The incident comes on the heels of a warning by former England captain Sol Campbell, who is black, to “stay home, watch it on TV... don’t even risk it” after BBC last month showed football fans in the two countries making Nazi salutes and taunting black players with monkey chants.